I've updated TurboSphere on github to include the BASS audio plugin (and updated the included docs accordingly). It includes the ability to use external soundfonts, and includes a demo font (Hollywood, which is terrible but tiny, only ~512k. But you can change the system.ini file, and replace it with anything you want). You can also play WAVs, OGGs, theoretically mod-music, and possibly a lot of other files (BASS can supposedly try to use system codecs if it can't open a file, but I haven't tested that). I also plan on adding general BASS plugin loading.
I don't have it working so that you can use the machine's system soundfont, because I can't test that yet. Fedora doesn't include a default MIDI soundfont, I haven't installed the stuff to make MIDI work at all on my Arch machine, and my Windows machine died recently (I'll cast res on it soon, once my mana recharges--aka, when I get enough money to buy the parts).
Right now all that has been added is:
new Sound(filename) //Sound
sound.Play([loop]);
sound.Stop();
This update also includes some of the new (actually restored after losing them when I switched to OpenGL) software surface primitives:
surface.Line(x1, y1, x2, y1, color);
surface.Rectangle(x, y, w, h, color);
surface.FilledCircle(x, y, r, color);
surface.OutlinedCircle(x, y, r, color);
I also slightly improved engine startup time and game loading time...which is probably overshadowed by now loading BASS and BASSmidi at startup.
To test the sounds with the new startup game, press M to play an ogg and N to switch and play a midi.